It's very impressive that you were able to write such a rich and well-developed story in just 2 days. The idea of a fractured world sundered by magic is fascinating, especially with how stark the difference between the two sides is and how those marked with the scars are treated. The way the families have to separate if a child is born from a different half of the world is an interesting albeit tragic consequence. The mission to get the mushrooms that also gives us more exposition is a natural way to introduce it.
Looking forward to the completed version! ^^